OurBigBook is currently hardcoded to send emails with Sendgrid. That provider was very easy to get started with, and has a free plan suitable for testing. Setup is described at: OurBigBook Web email sending with Sendgrid. Patches supporting other providers in a configurable way are welcome.
In development mode, emails are all logged to the server stdout and not actually sent, unless you run as:
This can be used to test the email integration locally.
OURBIGBOOK_SEND_EMAIL=1 npm run dev
Some research of different methods is shown at: cirosantilli.com/send-free-emails-from-heroku